But what about high-paid knowledge workers? I have taught thousands of MBAs at many of the world's top business schools and I estimate that this is equally true of them. They do not complain loudly because they have all the accouterments of a "successful" life but their suffering is real. Many feel stuck and helpless and grin and bear it.

Here is a tale of one who burst out by discovering his entrepreneurial self. (I hope that this will serve as an inspiration for you even if you are not really disengaged but would just like to reach your full potential.)

Randy Shuken was the chief of staff to the CEO of Master Card. It was a high visibility, high influence position that he enjoyed. And then a new CEO came in and started to bring his own team in. Shuken was sidelined. He had the option of remaining at his current level of seniority and compensation but that would require moving internationally. He was well settled in his community and his family did not want to relocate.

He quit.

And then there were days of angst as he networked. He joined the board of a small company in the e-commerce and logistics space and it was like a refreshing tonic. Decisions were made fast and implemented right away. His previous experience was with large companies where the pace was glacial.

The experience was therapeutic and he started to feel that this was where he belonged. He was invited to speak at a Think Tank in Madrid and was wandering in the Salamanca area looking for hand-crafted items. He came across a basic store with plywood walls in an isolated area that offered shoes you could design yourself for a mere 100 Euros.

He was intrigued by how this could be done at such a low price so he dug deeper. Uge Saiz and Alvaro Sasiambarrena were in their early twenties and started in banking.

They hated it.

So they moonlighted with a shoe business on the side and eventually quit their day jobs to do it full time. Initially they sold shoes made by others and eventually decided to make their own. They couldn't agree on design so they agreed to let the customer decide.

But how could you make shoes individually?

Typically a shoe of a particular design and size was manufactured in a run of 100 to several thousand items. They devised an entirely different process where shoes could be made individually. Leather was cut one by one and you could move from a loafer to a boot to an oxford.

Shuken quickly realized that, if he could scale the manufacture, he had a potential blockbuster. America was the obvious market and he decided that online sales was the way to go. With his wife, Monica, he mad a list of more than a hundred shoe factories in Spain and they visited more than 30 of them.

They were interested in making the kind of shoes that you can buy and resole and keep for a lifetime, and assembled the infrastructure they needed for the scale they anticipated. One company to cut the leather, another to sew it and a third to construct the shoe. They created software to help a prospective buyer visualize the shoe and create excitement at the thought of owing a custom designed shoe for less than the cost of an off the rack product.

Randy and Monica soft launched the line in a series of 'pop-up' stores - local spaces in high traffic areas they occupied for a limited time. Local advertising enticed prospects and many simply walked in. They were exposed to the concept and could order via iPads.

They learnt a lot: What styles were popular? What did customers want that they did not have? Initially all shoes were shipped to their home and then they shipped to customers. When volume increased, they struck a deal with UPS and arranged for direct shipment to the customer from Spain.

Shuken thinks big. "We want to be the Warby-Parker of shoes," he explains. "We have eliminated entire layers of middle men to give the customer great value." Handmade shoes from factory to home is great but he is already thinking ahead. What's next? How about bespoke shoes made to fit your specific foot?

His team is developing an app that will permit three pictures of your foot against a standard object capture all the information needed to custom design a shoe just for you. A Kickstarter campaign is underway to finance this and further development. Will Quero, this upstart shoe company succeed? Who knows?

But in one way it has already succeeded. There is a spring to Shuken's step and a sparkle in his eyes. He has not felt this well and alive for years. And that is the feeling that I would like every one to have.